Recently, it has become fashionable to purchase new garments which have been treated by the manufacturer or a laundry to produce a worn, used, faded or distressed look. This is especially true for denim-based cotton fabric which is often treated before sale to produce a stone-washed look. That is, the garment is subject to a mechanical and/or chemical action or a combination of both to produce a faded, distressed or stone-washed look with random color variation in the panels and the seams of the garment. Typically, such a stone-washed look is formed by washing the garments in a liquid bath with an oxidizing agent along with pumice stone or synthetic stone.
Another example of a method of treating garments to produce a worn look is disclosed in Ricci, U.S. Pat. No. 4,740,213 where pumice is impregnated with an oxidizing agent such as sodium hypochlorite. These granules are tumbled with the garments to be treated in a rotating drum (not in a liquid bath) for a set period of time and then the oxidizing agent is neutralized by washing the garments. While this often produces a desirable look, sometimes called an "acid wash", there are numerous problems with this and the traditional stone-washed method, including problems with effluent, wear and tear on the machines and garments and the time consumed in treating the garments, both pre and post wash.
Garments, especially denim-based garments are occasionally treated in a liquid bleach bath to bring out or lighten up the fabric uniformly. Such treatment in a liquid bleach bath has been used in conjunction with both stone-wash and acid-wash treated garments. When stone or acid wash garments are treated in a liquid bleach bath, both the light areas and dark areas are uniformly brought out or lightened. That is, the use of bleaching out dye is well known for denim garments used either alone or in conjunction with other methods of treating garments.
Patents that address the problems set forth in treating garments with pumice or synthetic stones impregnated with an oxidizing agent to produce a stone-washed look include U.S. Pat. No. 5,215,543 (Milora et al. 1993) and U.S. Pat. No. 5,213,581 (Olsen et al. 1993). These two patents discuss at some length the problems associated with the traditional stone-wash method of treating garments.
Milora et al., address the various problems with the traditional stone-wash method of treating garments by providing compositions and methods wherein the integral masses of stones are provided having a chemical composition which is soluble in wash or rinse liquid for the fabric. The stones are of sufficient size and hardness to effect abrasion of the fabric without substantial disintegration of the pellets during tumbling in order to simulate the action of pumice stones.
Olsen addresses the problems by providing processes and compositions for obtaining a stone-wash, distressed or "used" look to clothing and utilizing compositions that are stone free by providing an aqueous composition containing amounts of a cellulase enzyme that can degrade cellulosic fabric and release the fabric dye or dyes.
Applicants' own patents to Dickson et al. U.S. Pat. Nos. 4,900,323; 4,919,842; and 5,190,562 disclose a bleaching composition for use in a non-aqueous method for fading denim fabric. U.S. Pat. No. 4,900,323 discloses a diatomaceous earth carrier for a bleaching composition, such as potassium permanganate, chlorine bleaches, and peroxygen bleaches. The non-aqueous method disclosed calls for tumbling the fabric with the bleaching composition.
U.S. Pat. No. 5,190,562 is a Continuation of U.S. Pat. No. 4,900,323 and also discloses a non-aqueous method for fading denim fabric. The bleaching composition in this later issued patent comprises a selected from feldspar, soda ash, sodium silicate, synthetic silica dioxides, calcium carbonate, sodium bicarbonate, sodium sequis carbonate, borax, and sodium sulfate, any of which are impregnated with potassium permanganate or other bleaching agent.
U.S. Pat. No. 4,919,842 discloses a bleaching composition prepared according to particular methods and comprising potassium permanganate, diatomaceous earth and water.
The above cited patents are simply a few of a number of patents related in the objective of producing a faded, distressed or stone-washed look to garments, typically denim or cotton garments, without the disadvantages set forth above.